1. Field of the Invention
The present invention relates generally to the field of electrical power load control systems and more particularly to a method and system for actively controlling power load management for individual customers and optionally tracking power savings for both the individual customer as well as the overall electric utility.
2. Description of Related Art
The increased awareness of the impact of carbon emissions from the use of fossil fueled electric generation combined with the increased cost of producing peak power during high load conditions has increased the need for alternative solutions utilizing load control as a mechanism to defer, or in some cases eliminate, the need for the deployment of additional generation capacity by electric utilities. Existing electric utilities are pressed for methods to defer or eliminate the need for construction of fossil-based electricity generation. Today, a patchwork of systems exist to implement demand response load management programs, whereby various radio subsystems in various frequency bands utilize “one-way” transmit only methods of communication. Under these programs, RF controlled relay switches are typically attached to a customer's air conditioner, water heater, or pool pump. A blanket command is sent out to a specific geographic area whereby all receiving units within the range of the transmitting station (e.g., typically a paging network) are turned off during peak hours at the election of the power utility. After a period of time when the peak load has passed, a second blanket command is sent to turn on those devices that have been turned off.
While tele-metering has been used for the express purpose of reporting energy usage, no techniques exist for calculating power consumption, carbon gas emissions, sulfur dioxide (SO.sub.2) gas emissions, and/or nitrogen dioxide (NO.sub.2) emissions, and reporting the state of a particular device under the control of a two-way positive control load management device. In particular, one way wireless communications devices have been utilized to de-activate electrical appliances, such as heating, ventilation, and air-conditioning (HVAC) units, water heaters, pool pumps, and lighting, from an existing electrical supplier or distribution partner's network. These devices have typically been used in combination with wireless paging receivers that receive “on” or “off” commands from a paging transmitter. Additionally, the one-way devices are typically connected to a serving electrical supplier's control center via landline trunks, or in some cases, microwave transmission to the paging transmitter. The customer subscribing to the load management program receives a discount for allowing the serving electrical supplier (utility) to connect to their electrical appliances and deactivate those appliances during high energy usage periods.
While one-way devices are generally industry standard and relatively inexpensive to implement, the lack of a return path from the receiver, combined with the lack of information on the actual devices connected to the receiver, make the system highly inefficient for measuring the actual load shed to the serving utility. While the differential current draw is measurable on the serving electric utility's transmission lines, the actual load shed is approximate and the location of the load deferral is approximated at the control center of the serving utility.
One exemplary tele-metering system is disclosed in U.S. Pat. No. 6,891,838 B1. This patent describes details surrounding a mesh communication of residential devices and the reporting and control of those devices, via WANs, to a computer. The stated design goal in this patent is to facilitate the “monitoring and control of residential automation systems.” This patent does not explain how a serving utility or customer could actively control the devices to facilitate the reduction of electricity. In contrast, this patent discloses techniques that could be utilized for reporting information that is being displayed by the serving utility's power meter (as do many other prior applications in the field of tele-metering).
An additional exemplary tele-metering system is disclosed in U.S. Patent Application Publication No. 2005/0240315 A1. The primary purpose of this published application is not to control utility loads, but rather “to provide an improved interactive system for remotely monitoring and establishing the status of a customer utility load.” A stated goal of this publication is to reduce the amount of time utility field personnel have to spend in the field servicing meters by utilizing wireless technology.
Another prior art system is disclosed in U.S. Pat. No. 6,633,823 B2, which describes, in detail, the use of proprietary hardware to remotely turn off or turn on devices within a building or residence. While initially this prior art generally describes a system that would assist utilities in managing power load control, the prior art does not contain the unique attributes necessary to construct or implement a complete system. In particular, this patent is deficient in the areas of security, load accuracy of a controlled device, and methods disclosing how a customer utilizing applicable hardware might set parameters, such as temperature set points, customer preference information, and customer overrides, within an intelligent algorithm that reduces the probability of customer dissatisfaction and service cancellation or churn.
Attempts have been made to bridge the gap between one-way, un-verified power load control management systems and positive control verified power load control management systems. However, until recently, technologies such as smart breakers and command relay devices were not considered for use in residential and commercial environments primarily due to high cost entry points, lack of customer demand, and the cost of power generation relative to the cost of implementing load control.
One such gap-bridging attempt is described in U.S. Patent Application Publication No. US 2005/0065742 A1. This publication discloses a system and method for remote power management using IEEE 802 based wireless communication links. The system disclosed in this publication includes an on-premise processor (OPP), a host processor, and an end device. The host processor issues power management commands to the OPP, which in turn relays the commands to the end devices under its management. While the disclosed OPP does provide some intelligence in the power management system, it does not determine which end devices under its control to turn-off during a power reduction event, instead relying on the host device to make such decision. For example, during a power reduction event, the end device must request permission from the OPP to turn on. The request is forwarded to the host device for a decision on the request in view of the parameters of the on-going power reduction event. The system also contemplates periodic reading of utility meters by the OPP and storage of the read data in the OPP for later communication to the host device. The OPP may also include intelligence to indicate to the host processor that the OPP will not be able to comply with a power reduction command due to the inability of a load under the OPP's control to be deactivated. However, neither the host processor nor the OPP determine which loads to remove in order to satisfy a power reduction command from an electric utility, particularly when the command is issued by one of several utilities under the management of a power management system. Further, neither the host processor nor the OPP tracks or accumulates power saved and/or carbon credits earned on a per customer or per utility basis for future use by the utility and/or customer. Still further, the system of this publication lacks a reward incentive program to customers based on their participation in the power management system. Still further, the system described in this publication does not provide for secure communications between the host processor and the OPP, and/or between the OPP and the end device. As a result, the described system lacks many features that may be necessary for a commercially viable implementation.
Therefore, a need exists for a system and method for active power load management for individual customers that is optionally capable of tracking power savings for the individual customer as well as the electric utility to thereby overcome the shortcomings of the prior art.